Which 7mm ??? picture of new case added

dan belisle said:
I find it interesting that the WSM can equal the ballistics of the STW, and recoil less. All from a much smaller case. Interesting. - dan
Click to expand...

me too...that's pretty impressive,...the WSM must be cut from the same cloth as the 280 Ackley....:rolleyes:..afterall,...the 280AI routinely bests the 7mm Rem Mag in velocity while running about 10 grains less powder...:rolleyes:

maybe they have a 36" barrel..?:D...and a 15 pound rifle....;)
 
I dont think so if i recall and i will have to check in my reloading notes i was pushing a 139 gr at well over 3400 fps without big pressure sign, extraction was stiff but accuracy was awsome.... no WSM can achieve that pretty sure... JP.
 
I was reloading (find my notes ) 175 gr nosler at 3120 fps so you could be right about equaling the STW with the WSM, like i said it is retired in the back of my gun safe, it became kind of an obsolete rifle for me since i shoot so many 308 and now lately i am hooked on my 6.5 Creedmoor... Thank. JP.
 
caramel said:
I dont think so if i recall and i will have to check in my reloading notes i was pushing a 139 gr at well over 3400 fps without big pressure sign, extraction was stiff but accuracy was awsome.... no WSM can achieve that pretty sure... JP.
Click to expand...

How about 3312fps with a 140gr bullet with no pressure signs and easy extraction? Great accuracy, too.
 
Still a 100+ fps difference, the STW was ahead of is time for a while but i do agree, it is kind of to much of a barrel burner, i ran 3 barrels on my STW so obsolete it is now for me... JP.
 
Here is a picture of what I think might work good please all feedback welcome.

This is a casing I formed from a 300 ultramag shortened up next to a 22br the powder capacity is 58gr of varget a 308 is 47gr and a br is 33gr at the neck shoulder junction.

It is basically a scaled up br.

Now I don't have any idea how fast it would push a 180gr vld but my guess is 2900 fps .
I am trying to mimic a br by scaling it up and am hoping it will group very tight.

A friend of mine is going to drop me off some 7mm saum casing so I can compare and try and reform some of these as well,also I can measure the capacity of both cases .

ruger77222.jpg
 
coyote said:
Here is a picture of what I think might work good please all feedback welcome.

This is a casing I formed from a 300 ultramag shortened up next to a 22br the powder capacity is 58gr of varget a 308 is 47gr and a br is 33gr at the neck shoulder junction.

It is basically a scaled up br.

Now I don't have any idea how fast it would push a 180gr vld but my guess is 2900 fps .
I am trying to mimic a br by scaling it up and am hoping it will group very tight.

A friend of mine is going to drop me off some 7mm saum casing so I can compare and try and reform some of these as well,also I can measure the capacity of both cases .

ruger77222.jpg
Click to expand...

You have created a shorter fatter RSAUM. performance will be similar. So will a 280 improved.

Case shape doesn't really affect accuracy at this level of kaboom. Case volume will determine max potential speed.

The barrel will determine if you can use that speed accurately.

Jerry
 
Jerry I'm not convinced performance is always the same but it may.
Over the years a lot of diferent cartriges have hit the market some good some so so and some no good.

There seems to be an accuracy node in short fat cases 6br, 6ppc even the 7saum , 300saum , I have shot both a 7saum and a 7rem mag the saum is almost as fast but it seems to group better.
Now a case with less powder almost matches the speed and is more accurate,I think a 7rsaum could group tighter if it was a bit shorter I could be wrong though.
 
Had a chance to play with varying case shape vs accuracy while maintaining similar capacities. Results showed no gain accuracy due to shape BUT what did matter when going from varying case volumes was being able to find a suitable powder to make that case volume rock.

There were certainly some case volumes that matched available powders better and that lead to better performance but now there are so many more powders that it is harder to find a 'bad' case volume then not.

If short fat was where it was at, why does the 300Wby and its many variants hold so many 1000yds BR records?

My smallest 1000m group shot on paper and scored was with a 7RM.

Jerry
 
Mystic Precision said:
Oh, I dunno. Just depends on how you load either.

having say 15% more case volume gotta be good for something.

Jerry
Click to expand...

I'm pretty sure given equal barrels and equal pressures the larger case will drive an equal bullet faster every time. But I'm old school and don't know much about magic case shapes and special powders. Always willing to experiment though. Keeps me young(er). - dan
 
Maybe I should just go with a 7 saum and get it over with but I love wildcating lol.
What kind of barrel life can one expect from a 7saum 2000 rnds maybe?

I know a 284 is supposed to last quite a few rounds like 3000 from what I have been reading.
 
Go with the 7 SAUM. If you are hunting, you won't wear it out. If you are a competitor, there will always be several on the line with new barrels, and a 2year old barrel won't cut it. It will put you at a disadvantage. Barrel life is a cost of competing. It shouldn't be a major factor in your cartridge choice for F(O).

Less reading, more shooting.

NormB
 
A 7mm WSM is running between 600 and 800 rounds for barrel life on 'F' class match rifles so I suppose the 7mm SAUM will run a bit more in competition since the case capacity is slightly less. Hunting rifles would last a lifetime.

Steve
 
SteveB said:
A 7mm WSM is running between 600 and 800 rounds for barrel life on 'F' class match rifles so I suppose the 7mm SAUM will run a bit more in competition since the case capacity is slightly less. Hunting rifles would last a lifetime.

Steve
Click to expand...

That is very short barrel life it would be hard to make it through one season.

Does anyone know how much longer a saum would go.
 
You must log in or register to reply here.
Back
Top Bottom